Mega Gengar is the format’s highest-impact trapping Mega. Shadow TagShadow TagabilityPrevents both opposing Pokémon from switching out. Trapped Pokémon must either attack, use status moves, or get KO'd.Click to read more → prevents every opposing Pokémon from switching out — both of them simultaneously in a doubles battle. The opponent’s entire repositioning game is gone the moment Gengar Mega Evolves. Whatever they have in front of you is what they fight with until Gengar faints or retreats.
This is a fundamentally different kind of power than raw damage. It doesn’t matter how hard Gengar hits if the opponent could just pivot away — except they can’t. Shadow Tag turns every matchup into a fight to the death.
How trapping works in doubles
In standard singles play, trapping means one Pokémon is locked in against one opponent. In doubles, Shadow Tag traps both opposing Pokémon at once. An opponent who would normally bring in a counter to Gengar, or pivot to a better matchup after one of their Pokémon goes down, loses that option entirely.
This creates enormous decision pressure. Opponents must commit to their current field position and execute their game plan without any pivoting. Good players using Gengar exploit this by setting up long-term board advantages — a trapped opponent often has to use ProtectProtectmoveA move that makes the user immune to all moves for one turn. Fails if used consecutively.Click to read more → or other stalling tools just to create breathing room.
Shadow Tag does not affect teammates
Your own Pokémon can still switch freely. Only the opponent’s side is locked in. This asymmetry lets Gengar’s team pivot around it: a teammate can retreat to a different member while the opponent stays trapped, essentially granting free repositioning to Gengar’s side every time it’s active.
Offensive profile
Ghost/Poison is a strong offensive typing. Shadow Ball (Ghost STABSTABmechanicSame-Type Attack Bonus: a move deals ×1.5 damage when its type matches one of the user's types.Click to read more →) and Sludge Bomb (Poison STAB) cover most neutral targets. Gengar also has extremely high Special Attack (170 after Mega EvolutionMega EvolutionmechanicOnce per battle, a Pokémon holding the right Mega Stone transforms into a stronger form with new stats, type, and ability.Click to read more →) and good Speed (130), which means it can often take the KO it’s looking for before the opponent can respond.
Will-O-WispWill-O-WispmoveBurns the target — halving their physical Attack and dealing 1/16 max HP chip damage every turn.Click to read more → and Hex are another common combination — burn the opponent with Will-O-Wisp, then use Hex, which doubles in power against a Pokémon that has a status condition.
What stops Mega Gengar
- Ghost-type moves from the opponent — Shadow Tag doesn’t protect Gengar from taking damage. A faster Ghost attacker or priority Ghost move threatens it directly.
- Dark-type moves — Ghost/Poison means Dark hits for 2×. Any Pokémon carrying Dark-type coverage can pressure Gengar hard.
- Ground moves — Ground ignores Gengar’s Ghost typing and hits the Poison type for neutral. Wait — Gengar is actually immune to Ground due to Levitate in its base form, but in Mega form it loses Levitate. Mega Gengar has no Ground immunity. Earthquake hits it for neutral damage, and Precipice Blades or similar powerful Ground moves land cleanly.
- Fainting Gengar — When Gengar faints, Shadow Tag ends. Opponents who can burst it down before it traps effectively end the lock early.